High dbaji



April 19,- 1932. F. CASABLANCAS 1,854,691

HIGH DRAFT MECHANISM PROVIDED WITH ENDLESS BELTS Filed Aug. 12, 1930 2 Sheets-Sheet l HIGH DRAFT MECHANISM PROVIDED WITH ENDLESS BELTS Filed Aug. 12, 1930 2 Sheets-Sheet 2 Patented Apr. 19, 1932 PATENT orrlcs FERNANDO CASABL ANCAS, OF SAIBADELL, SPAIN HIGH DRAFT MECHANISM PROVIDED WITH ENDLESS BELTS Application filed August 12, 1980, Serial No. 474,848, and in Spain September 28, 1929.

In the drawing mechanisms with three airs of cylinders of which the centre one is provided with endlesslelts, the principal draft takes place (as in the system without belts) between the centre pair which is the one carrying the endless belts and which actuates as fibre retaining mechanism and the front pair which actuates as draft mechanism. Nevertheless, in order to reduce the 1 twist of the sliver and leave its fibres slightly slack, it is usual also to'draw somewhat between the back pair of feeding cylinders, which act in this case as retainers, and the intermediate pair with or w thout endless belts which act as drawers. In order that this preliminary draft may be efficient, it is necessary to impart to the intermediate cylin-' ders a pressure greater than would be necessary for the belts to act simply as retainers for the principal draft which takes place between the endless belts and the front cylinders.

This excess of pressure in the draft mechanisms with endless belts has no inconvenience in the case of narrow belts of slow speed as in the case of spinning frames, but in the case of wider belts used in preparing machines as in the speed or fly framesand in particular in thedrawing frames, where the belts have a high speed, difiiculties arise in particular in the lateral guidance of the belts due to the above-mentioned excess of pressure. In the machines with four pairs of cylinders, as in drawing frames for joining come by carrying out the partial or preliminary draft between the two first pairs of cylinders in such manner that between the toothed crowns placed outside the endless and drawing, these difliculties may be over-' second pa r of cvlinders and the third pair,

cases is possible since the sliver is supplied to these machines very loose and. without twist.

In these diflerent ways, it is possible in racticc to diminish the load or pressure actmg on the cylinders carrying the belts up to the point necessary so that the belts effect the retention of the sliver under the best conditions. Nevertheless, diminishing. the pressure on the cylinders in this manner presents $9 on'e disadvantage which is that as the upper belt and its cylinder have no positive movement but are rotated by contact with the movable belt below and this is carried in its turn by contact with its cylinder, the pressure which is suitable for properly retaining the fibres is not suflicient to ensure the continued rotation of the upper cylinder and this causes great inconveniences and defects in the homo .geneity of the flow of fibre and in the thread or sliver obtained.

The improvement forming the object of the present invention overcomes this difliculty and consists in fitting the cylinders carrying the endless belts, both top and bottom, with belts, so that the movement of the up er cylinder is effected positively in place 0 its being transmitted by the lower cylinder. with the interposition of the belts and the fibres which are being worked.

The application of the improvement forming the object of this patent is shown on the annexed drawings.

Figure 1 shows in section on the line I-I of Figure 2 a draft mechanism of ajoining and drawing bench called a drawing frame composed of four pairs of cylinders and end- 4 less belts.

' Figure 2 shows the same mechanism in section on the line II--II of Figure 1.

Figure 3 shows in section on the line II I III of Figure 4 a draft mechanism of a slabbing frame with four pairs of cylinders, and endless belts.

Figure 4 shows the same mechanism in lan. p In Figures 1 and 2 is shown a draft mechanism with four pairs of cylinders, in which the cylinders 12 carry the belts 34, which 1 retain the fibres and carry them to the front or drawing pair of cylinders 12. At the back part of the mechanism there are two other pairs of cylinders 13-14,between which is effected the preliminar draft to diminish the twist of the sliver. The cylinders 12 have at both sides of the endless belts and forming part with the said cylinders, the toothed wheels 11 and 21 whose ratio of engagement corresponds to the respective diameters of the cylindersl and 2. In this wa it is possible to transmit movement exact y to the cylinder 2 without any displacement taking place relatively'in the two belts, although the pressure exerted on the neck of the cylinder 2 is a minimum.

This mechanism also presents peculiarities of construction of the support 6 in which are carried the endless belts, owing to its extra width. The side plates 63 of this support which are of normal type, are connected by bolts 64 to thick foundation plates 62 which are held firmly by means of a cross bar 61 inserted in them under pressure with its ends. The plates 63 have edges 631 to guide the lower belt and avoid this folding over its edges downwards when moving sideways.

The end spindles 22 of the cylinder 2 are carried in bushes 5 which in turn are carried in the shaft supports of the drawingmechanism by means of fiat parts52 which impede their rotation. These bushes have necks or recess parts 51 over which are fitted the bars giving pressure to .the cylinders.

The mechanism of Figures 3 and 4 is similar to that of Figu i'es 1 and 2, and also comprises a pair of, cylinders 1 and 2 carrying the belts 3 and 4'between the plates of the support 6, and these belts supply the fibres to the front drawing cylinders 12 through the floating reducer 8 of known construction. The cylinders engage together through the toothed crowns 11 and 21, the diameters of which are proportional to the diameters of the eriphery-of the cylinders 1 and 2 which wor z with the endless belts 3 and 4.

In Figure 4 will be seen the details of construction of the meshing wheels. Since the upper cylinder 2 carries an endless belt at each of its ends, the most suitable place for the toothed wheels 11 and 21 is its centre or neck part as shown on the drawing. The pressure bar which would act on the exact spot in which are situated the toothed gear ing 21, is constructed in the form of a twopronged fork bearing one on each side of the toothed crowns. This bar has not been drawn in order not to complicate the figure.

From the above description it will be readily appreciated that the pressure exerted be tween the cylinders 1 and 2 may be very light and only sufficient for the purpose of holding the slivers properly between the belts 3 and 4. The actual driving operation of the cylinders and the belts in relation one to another frames, the combination with upper and lower cylinders with co-operating belts thereon and relatively light pressure means between the cylinders, intermeshing gear wheels on the cylinders proportioned relative to the cylinders for driving the same and the belts thereon independently of any frictional contact between the belts due to said light pressure.

2. In a drawing frame, a high draft mechanism having endless belts to conduct the sliver to the drawing cylinders, a pair of cylinders to drive said endless belts, pressure means acting on the upper cylinder of said pair of cylinders to exert upon the belts a very light pressure in itself insuflicient to insure the motion of the belts, intermeshing toothed wheels mounted on said pair of cylinders topositively transmit motion from the lower cylinder to the upper one and thus insure a proper motion of the belts ir; respective of the light pressure therebetween.

In testimony whereof I have signed my name to this specification.

FERNANDO CASABLANCAS. 

